1. Field of the Invention
The invention relates to a punch for use in molding a workpiece.
2. Description of the Related Art
Various molds and molding methods using the molds have been proposed in order to mold a workpiece. For example, JP S57-208250 A has disclosed a method of producing an inkjet nozzle from an orifice back sheet and an orifice sheet and a punch used in the method. This method of producing the inkjet nozzle is carried out as follows. A tip end portion of a conical punch is pressed against a sheet placed on a die to thereby form concave portions shaped in accordance with the shape of the tip end of the punch in the sheet. Then, convex portions formed on a surface of the sheet opposite to the surface against which the punch is pressed are ground by a lapping machine to thereby form fine holes in the sheet. In this manner, an orifice back sheet is produced.